So I got the error "Heads up! Couldn't open this project" and did research and found out that it is a generic error, then looked up the exact error on this site: https://legoapptools.azurewebsites.net it showed me this error:

#WARNLONESTK1 Lonely stack ev3move_rotation-wheel()
#WARNLONESTK1 Lonely stack procedures_call()
#WARNLONESTK1 Lonely stack ev3sound_playSoundUntilDone()

I understand that the problem is that I have Blocks floating in my project, but I don't know how to fix it. Here is a link to the project file: https://www.dropbox.com/scl/fi/aqsg90fv7mptqmi1o5zhc/WRO2024-1.lmsp?rlkey=nd6j1b8dlcrt45iadyqy5ri2d&dl=0

  • The Lonely stack is not an error. This particular file contains a null value in a list which isn't valid. I updated my answer at bricks.stackexchange.com/a/16945/3498 to describe how to fix this. Mar 23 at 17:35
  • Here is a link to the repaired file WRO2024 1 - fixed.lmsp. Mar 23 at 17:39
  • @DavidLechner thank you very much I saw you're answer to the other post but I couldn’t solve it on my own. You are a life saver! I hope they will add an easier solution to this. Greetings Jonathan
    – Joni
    Mar 26 at 10:38


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